It would be easy to conclude that Zinedine Zidane doesn't have anything to prove.

The Frenchman sauntered in from Real Madrid's second team in January with a job that he couldn't possibly fail. Rafael Benitez's squad was painted as a mess and his reign as a disaster, meaning that if Zidane could pull Madrid even into distant sight of their arch rivals at the top of La Liga it was to be a magnificent job.

If he couldn't, Zidane was a victim of a terrible situation and, depending on how effective the Frenchman had been with the defibrilators and Madrid's rotting, diamond-encrusted corpse, could be afforded a chance at the big job.

Had Zidane taken the Bernabeu club further down the table then his inexperience would be glossed over and a big name, probably Jose Mourinho, could have slid onto the throne.

But what happened was stranger than fiction, albeit a fairytale for the rookie coach.

A good squad led by a coach with impressive temperament, an understanding of how to motivate elite players and a satisfactory tactical knowledge was enough to bring Madrid to glory less than six months after taking his first top-level job.

But Luis Enrique has seen it all before.

The Barcelona boss took a similar path to the first team as Zizou, but made a stop in Vigo with Celta for one season. His work in Galicia was enough to convince the Nou Camp hierarchy to bring him back and his first season brought five trophies in a haul only beaten by Pep Guardiola's debut campaign with the senior side.

However, cast your mind back and you may remember that Luis Enrique wasn't exactly happy after that season and made the suggestion more than once that he might leave the club. Last season he continued that, hinting that he'd be ready to take the Spain job should he be approached about replacing Vicente Del Bosque.

The Barca boss has never been completely clear about his long-term future (Image: REUTERS)

Luis Enrique has won La Liga in both of his seasons as Barcelona boss. He's won the Copa del Rey in both too and, like his rival in Madrid, the Champions League at his first attempt.

But just in case Zidane was still floating on a cloud from that night at San Siro in May, he need only look at the man in the opposing dugout this weekend to see how his future could pan out.

Real Madrid isn't a club that's particularly renowned for having long-term coaches and Florentino Perez was ready to bin Zidane as second-team coach just a couple of months before he bounced him into the big job.

It would have surprised nobody if the Frenchman had struggled this season and the Bernabeu had seen yet another mid-season reshuffle. Only a fool would categorically rule out it happening before the end of the campaign.

But at some point we may have to come to terms with the fact that Zidane is a good coach.

It must be easy to get your first job and be handed a raft of superstars, of that there is no doubt.

And yet, look what Benitez could do with the same squad. Look how things fell apart with Carlo Ancelotti. Remember how Jose Mourinho struggled with the dressing-room factions.

Uniting the squad and getting them to play well may not sound like rocket science but at a club where balancing such egos may as well be as complicated as nuclear fission, Zidane has succeeded.

It will be his capacity to adapt that will define his reign and, probably, career.

Luis Enrique had all that initial success and then shifted the focus of his team from their star-studded midfield to the front three. Ivan Rakitic came in to replace Xavi, but in body only. His more energetic, direct style complemented how Luis Enrique wanted the next iteration of Barca to look.

But the reality for both of them is that prospects at superclubs like Real Madrid and Barcelona may not be exactly long-term.

Luis Enrique has done outstanding work at Barca, but it's already looking troubled again (Image: AFP/Getty)

As Guardiola did, Luis Enrique could walk away from the club (Image: Shaun Botterill)

These two sides are now in the position where they are both expected to win every trophy they compete for. Maths alone tells you that this isn't possible.

Zidane is still in the warm afterglow of Milan, he's running clear at the top of La Liga and heads into el clásico with his side unbeaten in 25 league games but should he not return a single piece of silverware by the end of the season he may be out of a job.

Luis Enrique, who still might win everything this summer, is currently under that sort of pressure.

There is no talk of the sack, as there was on that January night in San Sebastian during his first season in charge. Defeat at home to Madrid could change that though. These are clubs who have assembled historically-strong squads and are determined, nay, obsessed with staying on top. It's far easier to change a coach than a £1billion roster of superstars.

Which brings us back to the beginning. It would, indeed, be easy to conclude that Zinedine Zidane doesn't have anything to prove.

But that would ignore the very nature of the club he manages, of either of these superclubs in an era when the gap between rich and poor (in all walks of life) has never been greater.

Success is how they will be defined, and the pre-match embrace between Zidane and Luis Enrique - for all their differences - will be one of the deepest mutual understanding. An understanding that after the glory must come glory. Or else.